The present invention relates to an integrated circuit including a detection circuit for detecting a bonding defect in a multi-bonding wire.
A multi-bonding structure known in the prior art uses a plurality of wires to connect a plurality of pads on an integrated circuit (IC chip) to a single lead terminal of a lead frame, which supports the integrated circuit (IC chip). Such a multi-bonding wire structure is used to improve product reliability particularly in power IC products used to control large currents. The integrated circuit undergoes inspection to test for wire breakage before being shipping from the factory as a product. However, a product including a multi-bonding wire structure would still be operable even if one of the plurality bonding wires connected to a single lead terminal is broken. In such a case, breakage of the bonding wire cannot be accurately determined using just an external testing device such as a tester that detects the resistance or voltage of the lead terminal.
To ensure product reliability, when one of a plurality of wires is broken in a product, that product must be determined as being defective. Japanese Laid-Open Patent Publication No. 2005-331516 describes a method that tests for wire breakage using an electric field sensor. However, with the art described in the above publication, bonding defects in an integrated circuit having a multi-bonding wire structure are not readily detected.